We present the results of a pilot near-infrared ( NIR ) spectroscopic campaign of five very massive galaxies ( \log ( \text { M } _ { \star } / \text { M } _ { \odot } ) > 11.45 ) in the range of 1.7 < z < 2.7 .
We measure an absorption feature redshift for one galaxy at z _ { \text { spec } } = 2.000 \pm 0.006 .
For the remaining galaxies , we combine the photometry with the continuum from the spectra to estimate continuum redshifts and stellar population properties .
We define a continuum redshift ( z _ { cont } ) as one in which the redshift is estimated probabilistically using EAZY from the combination of catalog photometry and the observed spectrum .
We derive the uncertainties on the stellar population synthesis properties using a Monte Carlo simulation and examine the correlations between the parameters with and without the use of the spectrum in the modeling of the spectral energy distributions ( SEDs ) .
The spectroscopic constraints confirm the extreme stellar masses of the galaxies in our sample .
We find that three out of five galaxies are quiescent ( star formation rate of \lesssim 1 M _ { \odot } ~ { } yr ^ { -1 } ) with low levels of dust obscuration ( A _ { V } < 1 ) , that one galaxy displays both high levels of star formation and dust obscuration ( { SFR } \approx 300 M _ { \odot } ~ { } { yr } ^ { -1 } , A _ { V } \approx 1.7 mag ) , and that the remaining galaxy has properties that are intermediate between the quiescent and star-forming populations .